 ## 字幕列表 影片播放

• - [Instructor] Hello.

• So we're told Colette rides her bike home

• from school every afternoon.

• She leaves school at 14:55 and arrives home at 15:25.

• How long does she ride her bike?

• So pause this video, like always,

• and see if you can answer that question.

• How long is her bike ride home?

• All right,

• now to help us answer that question,

• I'm going to set up a timeline.

• So that's my timeline there,

• and let's say that, let's see.

• Everything is going on between 14 hours

• and it looks like between actually past 15 hours

• so I'll go to 16 hours,

• so that is 14 hours

• and this is 15 hours

• and then 16 hours would be maybe right over here, 16 hours,

• and this would be 14 and a half,

• just to make things a little bit clearer.

• This would be 15 and a half, just like that.

• Actually, it'd be a little bit,

• it would be something like that,

• and so let's see.

• She leaves school at 14:55.

• Where is that on this timeline?

• Well, 14:55 is five minutes before 15,

• so it's going to be roughly right over here.

• So that is when Colette leaves,

• so that is 14:55,

• and then when she arrives, 15:25,

• that's 25 minutes after 15 hours,

• so that is right over there,

• so this right over there is when she arrives home, 15:25,

• and so how long is that?

• Well the way I think about it is

• if we go from 14:55 to 15,

• that is five minutes,

• so this part right over there is five,

• and then to go from 15 to 15:25,

• that's another 25 minutes.

• So the total,

• the total length of her trip in time

• is going to be five minutes plus 25 minutes.

• Five plus 25 is 30, 30 minutes,

• and we are done.

- [Instructor] Hello.

A1 初級